Ok, the reason your not getting the 9000+ score is basically the people over at MO are running for absolute best score they can get. They run totally "tweaked", altho they tweak for best performance, e.g. worst looking texture details etc.... Plus they run their video cards at insane overclocks (they use CPU heatsinks or watercooling, heck the guy that holds the highest true score (his name is macci) used a custom made phase-change cooler - i.e. same as a household freezer).
Also they only run the 4 game tests and nothing else, this is all that is required for 3dmark to create a score. Chances are the card are overclocked that high that it isn't stable enuff to complete the full series of tests.
As for your XP benchmark being higher than ME, basically ME is a pretty bad OS for most people, win98SE is faster (and usually more stable & compatible) than ME.
Hopefully this will shed atleast alittle light on the situation.
JayMan